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kvskv7
fire stops

I live in New England where the summers are oppressively humid and the winters springs are very wet and cold. I recently purchased an old colonial (1900) that is balloon framed (on a fieldstone foundation) currently without any insulation, and it needs fire stops. My question is in two parts: 1, Can I use 2lb closed cell polyurethane foam as a firestop, and if so, can I apply it directly to the interior of the sheathing in the bays as well as on the sill plate, without worrying about causing any of the wood to rot?

MLBSF
Re: fire stops

you can use it only if it's rated as a fire stop. i would just buy 1 bale of roxul fire stop, stuff it in each bay between the 1st and 2nd floor then you can insulate above and below it.

jkirk
Re: fire stops

or install wood blocking, thats the standard practice

Timothy Miller
Re: fire stops

Howdy- Whoa on thinking any foam is a fire block. It burns real good . You can use it as a air retarder/ insulator but then you need to encapsulate it with a fire rated product like drywall, or spray applied fire retardant...Edited- TO MAKE IT A FIRE STOP.
The post by MLBSF, rock wool is pretty easy to work with install friction fit.Before you get to insulated be sure no knob and tube wiring as you cannot insulate the cavities that have it otherwise house fire can result... Cellulose is fire rated and works swell in balloon framed walls and attics....

MLBSF
Re: fire stops

hi tim,

there is fire stop foam that i've used several times, made by the same company that makes the regular "great stuff" foam. i've used it, and had it approved by building inspectors, to fill small gaps up to about the size of a softball where ever firestopping is required.

JLMCDANIEL
Re: fire stops
Timothy Miller
Re: fire stops

Hold everything foam is not non combustible- IT IS COMBUSTIBLE. Foam colored orange/red it will combust the same as any other spray foam.

The air barrier of spray foam aids in the limiting of spread of flame by restricting oxygen.

What is the combustive temperature of spray foam?

LisaMorris
Re: fire stops

***, I just realized it now. Thanks for that info. I should have surfed the net.

jkirk
Re: fire stops

just a note. surfing hte internet for technical things such as fireblocking wont allows give you the correct information. if you do check the internet look for official government sites which post the building codes and how to fix this sort of thing.

i dont know how many times ive seen homeowners look things up and the information is nowhere near correct. i am saying this as a licensed carpenter who specializes in high end renovation and also worked in commercial construction where fire codes are highly enforced

canuk
Re: fire stops
jkirk wrote:

just a note. surfing hte internet for technical things such as fireblocking wont allows give you the correct information. if you do check the internet look for official government sites which post the building codes and how to fix this sort of thing.

i dont know how many times ive seen homeowners look things up and the information is nowhere near correct. i am saying this as a licensed carpenter who specializes in high end renovation and also worked in commercial construction where fire codes are highly enforced

Amen !!! :cool:

canuk
Re: fire stops
Timothy Miller wrote:

Hold everything Great Stuff foam is not what you think it is it has no fire rating. ITis is just foam colored orange/red it has no fire rating time so look out you are under the wrong impression.... read the label of each their can. The air barrier to smoke ---NOT FIRE BLOCK RATED!

Foam in a can is used in fire blocking proceedures -- not in so much that it is immune to burning --- rather for stopping air ( starving the fire of oxygen ) movement from on space to another.
Example --- where plumbing lines come up from the basement to the upper level --- the holes around the plumbing pipes need to be sealed if they will be enclosed in a wall cavity preventing air feeding oxygen to any potential fire.
The bright colored foam in a can is highly visiable for inspectors to easily see those pentrations have been sealed.

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